Fuel feeding system for motor vehicles



May 24, 1932. F. H. HEITGER FUEL FEEDING SYSTEM FOR MOTOR VEHICLES Original Filed May 25, 1925 um vl oz t w w Mud m, m NW N. v .wmw w Patented May 24, 1932 UNITED STATES PATENT oFFrcE FRANK H. HEITGEB, F FLINT, MICHIGAN, ASSIGNOR T0 MARVEL CARBURETER COM PANY, OF IIEIIIJTltlTIl', MICHIGAN, A. CORPORATION .OF INDIANA FUEL FEEDING SYSTEM FOR IHlIO'I-Ol'tv VEHICLES Application filed May 25, 1925, Serial No. 32,648. Renewed October 20, 1931. i

This invention relates to certain new and useful improvements in fuel feeding systems for motor vehicles and is a companion application of my ap lication filed even date herewith, the object eing to provide novel means for operating the piston of the pump so that the piston can be operated in such a manner that the operating means is free to move independent of the piston whereby the movement of the piston is controlled by the consumption of fuel.

Another and further object of the invention is to provide a fuel feeding system in which'the pump is provided with a collecting chamber. for col ecting the leakage past the iston whereby it can be returned to the inta e of the pump.

Other and further objects and advantages of the invention will be hereinafter set forth 90 and the novel features thereof defined by the ap ended-claims.

n the drawings, V Figure 1 is a vertical section through part of the system, part being shown in elevation;

95 and Figure 2 is a detail vertical section through the upper portion of the pump showing a slightly modified form.

In the drawings 1 indicates a charge form-'- ing device which is provided with a fuel bowl 2 in which is mounted a float 3- carr ing a valve 4 for controlling the inlet 5 t ereof, which is of the usual construction now in use so as to maintain a constant level within the float chamber of the char e forming device.

My improved construction of pump comprises a (pump barrel 6 havin an outlet 7 controlle by a spring presse check valve 8 which is connected by a pipe 9 to the inlet of thebowl 2 of the charge forming device.

The pum barrel is provided with-an inlet 10 contro ed by a spring pressed valve 11, said inlet being ada ted to be connected to a low level tank as s own in my companion application so that fuel can be drawn from the low level tank and forced directly to the bowl of the charge formin device.

The pump barrel is en arged to form a chamber 12 from which extends a passage 13 to a collecting chamber 14 in which is mounted a float 15 having a valve 16 controlling the outlet 17. The outlet is also controlled by spring pressed valve 18 and is in communication with the bottom of the pump barrel by branch 19, the tension of the sprin for holding the valve 18 in closed position Eeing less than the tension of the spring for holding the valve 11 seated so that when fuel is in the collecting chamber 14, it will be drawn into the pump barrel until consumed when the valve 11 will open on the suction stroke of the piston so as to draw fuel from the low level tank not shown. i

The float carries a rod-20 working through a plug 21 forming a closure for the upper end of the collectin chamber 14, said closure being provided wit a vent 22. 1

Slidably mounted within the pump barrel 6 is a piston 23 annularly reduced as shown at 24 to form in conjunction with the cham- 7o ber 12 an annular chamber in which the liquid which leaks by the piston is collected and flows by gravity into the collecting chamber 14. The upper end of the piston is provided with a vertical bore 25 enlarged as shown at 26, said enlargement being threaded to receive a plug 27 through which extends a piston 28 provided with a head 29 at its lower end working in the bore 25'. Said piston extends upwardly through a bearing 30 0' formed in a cap 31 forming a closure for the upper end of the barrel and is ivotally connected at 32 to a link 33 whic is ivotall connected to a wrist pin 34 carried y cran disc 35 adapted to be driven by a revolving part of the internal combustion engine to which the fuel system is applied or any other source of power whereby a rotary motion will be converted to-the crank disc 35 in order to reciprocate the piston.

Arranged in the upper end of the pump barrel above the piston is a coil spring 36' which is ada ted to be compressed when the piston 25 is drawn upwardly on the suction stroke so that when it is released by the piston rod which is loosely connected throughthe medium of the bore and plug, the sprin will force the piston down to discharge the iquid drawn within the barrel. j

The construction shown is for the purpose ing the piston and in constructing a fuel feeding lsystem 1n -drawn upwardly by the the pressure exerted by 65 therein has reac .let 1( and as the or loose connection between the piston rod ressure exerted on the outlet of the pump arrel is 'greater than the pressure exerted by the spring and the weight of the piston Joan remain in a raised position and the piston rod can operate back and forth in the bore through its loose connection without operatto force fuel out of the barrel accordance with my invention,

the fuel bowl 2 of the charge formlngdevice is so constructed that it over-balances the tension of the spring 36 and the weight of the piston 23 and maintains the valve in a closed position as long as the fuel within the bowl is maintained at a predeterminedlevel, whereby the outlet of the pump barrel remains closed so thatthe piston fails to reciprocate with the piston rod and is held in a raised position on the suction stroke until the pressure is reduced or untilthe liquid under the piston has leaked past the piston into the collecting chamber 14. As the float 15 in the collecting chamber closes the outlet of the collectin' chamber until the liquid ed a predetermined level, the pump does not begin to draw fuel from the collecting chamber until the float 15 raises to open the outlet valve.

In the operation of the fuel feeding system" is reciprocated o r iston rod, fuel is ecting chamber 14 as shown when the piston either drawn from the col or from the low level tank piston rod has raised the piston upwardly! against the tension of the spring, when t e. piston rod starts downwardly the lston will follow the piston rod so long as t e liquid within the bowl of the carbureter is be ow a and just as soon as the bowl raises above this predetermined level quid supp predetermmed level, the float 3 closes the inlet to the bowl and'the back pressure which is suflicient to overcome the tension of the l spring and the weight of the piston prevents fuel from the low the'piston from. moving downwardly and through its rod, the piston rod continues to reciprocate back-and forth without operating thepiston and of course,

receiving chamber. K 7

When in this position the fluid under the piston gradually leaks by the piston into the collecting chamber and the'piston slowly falls until it is againpi cked up by the piston rod and raised and starts the pump to operate again and the operation of the pump being determined by the-consumption of fuel by.

the charge forming device, as by the construction ofconnecting the piston rod loosely to the piston, the piston rod continues to through the in-' 1y to thethe pump fails to raise the level tank or from the reciprocate while the piston remains stationary. In the modification shown in Figure 2, the pump barrel 40 carries a cap 41 at'its u per end provided with a slot 42 through whlch extends a piston rod43 which is pivotally mounted on a wrist pin 44 of the crank disc 45, said piston rod being provided with'a spherical head '46 which is-loosely mounted in a bore 47 formed in the piston 48, said rod working through a plug 49 carried by the piston so as to form a loose or sliding connection between the piston rod and piston, whereby the iston rod is allowed to reciprocate back an forth without forcing the piston 'downwardl when the back'pressure is greater than t e pressure exerted b the spring 50 disposed above the piston 4 From the foregoing description it will be seen that I have provided a fuel pump employing a reciprocating piston operated-by mechanical means through a piston rod which has a sliding connection with the pis- ,the same, in connection with 'a collecting fuel as the piston is' free to move inde downward and it is agam picked up ed in sai piston formoving chamber which collects the fuel leakin past the piston so that it can be drawn back into the pumpvbarrelr -By this articular construction of pump with the plston loosely connectedto its operating means, the movem nt of the piston is entirely controlled by th consumption of ently of the operating means so that i em a small amount of fuel is being consume the piston may only move a slight distance or a short stroke on each revolutlon of the operating means and the distance of travel of thepiston is determined by the consumption of fuel, as if the discharge from the ump is restricted, the piston will not f0 ow the head on its downward stroke and as the fuel is consumed, the spring forces the iston y the o erating means so that the movement of the I loose connection with the piston P piston is entirely controlled by the consumpis supplied to the charge all times without an over-supply.

What I claim is 1. A pumping ing systems comprisin a pump barrel hav-' ing a .slidably moun (piston,-a s for '1 moving said iston to ischar el m said pum an a pistonrod sli ably mount-- said piston on the suction stroke for com ressmg' said spring, the movement of. said piston being controlled bythe consumption of fuel. l

2'. A pumping mechanism for fuelfeedin'g systems for motor vehicles comprising a.

mechanism for fuel feedtion of fuel so that an ample suppl of fuel ormmg evi'ee at v pump barrel, a piston slidably mounted in said pump barrel, a spring disposed above said plston within said barrel, said piston bemg provided with a vertical bore, an apertured plug for closing said bore vand a piston rod passing through the aperture of said plug having a head working 1n said bore forming a loose connection between sald p1s- 'ton and said piston rod.

signature.

' FRANK H HEITGER. 

